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Zhou Y.-F.,Renmin University of China | Zhou Y.-F.,Shanxi Academy for Environmental Planning | Zheng X.,Renmin University of China | Lei Y.,Renmin University of China | Chen D.,Renmin University of China
Huanjing Kexue/Environmental Science | Year: 2012

A series of static adsorption experiments by activated sludge were conducted for virus removal with f2 bacteriophage, which was seeded with a high concentration as surrogates for human enteric viruses. Adsorption kinetics had shown equilibrium conditions were established in some 120 minutes and the activated sludge could get rid of more than 96% f2 bacteriophage, with 85% of total adsorption occurring in less than an hour. Freundlich isotherm model adequately described the adsorption which indicated that the removal mechanism of virus is based on a multilayer adsorption in such a heterogeneous aqueous solution system. Adsorption capacity was found to vary with pH value, metallic cation concentration and organic content in wastewater, demonstrating the importance of these parameters for the removal of virus. Source

Shao Q.,CAS Beijing Institute of Geographic Sciences and Nature Resources Research | Fan J.,CAS Beijing Institute of Geographic Sciences and Nature Resources Research | Liu J.,CAS Beijing Institute of Geographic Sciences and Nature Resources Research | Huang L.,CAS Beijing Institute of Geographic Sciences and Nature Resources Research | And 18 more authors.
Dili Xuebao/Acta Geographica Sinica | Year: 2016

In this paper, we developed a series of assessment indexes based on the evaluation of ecological effects, which consists of the ecosystem structure, qualities, services, and main impacting factors for these changes. Comprehensive monitoring and assessment methods that focused on the planning objectives of ecological conservation and restoration project were developed based on field observation, remote sensing monitoring and quantitative simulation of ecological processes. Then we assessed the ecological effects of the first- stage of ecological conservation and restoration project in Sanjiangyuan region by adopting the trend analysis of dynamics in ecosystem structure and services. The results showed that since the beginning of the project eight years ago, the macro- situation of ecosystem in this region has been getting better but not reached the best situation in the 1970s. The continued degradation trends of grassland have been initially contained, but it is difficult to achieve the expected objective of "the vegetation coverage of grassland increasing by an average of 20%-40%". The wetland and water-body ecosystems have been restored. The water conservation service of ecosystem and water supply capacity of watershed were increased, and the volume of ecosystem water conservation reached the objective of increasing by 1.32 billion m3. The ecological restoration in the project regions tended to be better than that outside the project regions. In addition to climate change, implementation of the ecological conservation and restoration project had obvious and positive effects on vegetation restoration. However, the degradation situations of grassland were not fundamentally reversed, and the implementation of the project has not been curbing the increasing trend of soil erosion. Therefore, the local and preliminary characteristics of the first-stage of the project highlighted the long-term and arduous ecosystem conservation and protection in the Sanjiangyuan region. © 2016, Science Press. All right reserved. Source

Zhu H.,Beijing Forestry University | Sun P.,Shanxi Academy for Environmental Planning | Wen X.,Tsinghua University | Huang X.,Tsinghua University
Huanjing Kexue Xuebao/Acta Scientiae Circumstantiae | Year: 2011

We studied membrane organic fouling during microfiltration with secondary effluent organic matter (EfOM). The effects of pre-ozonation on the characteristics of EfOM and on EfOM membrane fouling were also investigated. The results show that hydrophilic substances (HIS) have a higher fouling potential due to a higher content of macromolecular and carboxylic groups and also higher soluble microbial products (SMP) or SMP-like substances. Pre-ozonation of EfOM increased the amount of carboxylic and phenolic groups, which could have aggravated membrane fouling. However, the reduction of dissolved organic carbon (DOC) (including the mineralization of small organic molecules) and the breakage of large molecules are suggested to be the major criteria for fouling reduction. Source

Sun P.-C.,Shanxi Academy for Environmental Planning | Li X.-L.,Shanxi Academy for Environmental Planning | Cheng G.,Shanxi Academy for Environmental Planning | Lu Y.,Tsinghua University | And 2 more authors.
Huanjing Kexue/Environmental Science | Year: 2014

According to the Stockholm Convention, polychlorinated dibenzo-p-dioxins/dibenzofurans (PCDD/Fs) and dioxin-like polychlorinated biphenyls (DL-PCBs) are classified into unintentionally produced persistent organic pollutants (UP-POPs), and named dioxins. Coke production as a thermal process contains organic matters, metal and chlorine, is considered to be a potential source of dioxins. Intensive studies on the emission of dioxins from coking industry are still very scarce. In order to estimate the emission properties of dioxins through coke production, isotope dilution HRGC/HRMS technique was used to determine the concentration of dioxins through flue gas during heating of coal. Three results were obtained. First, total toxic equivalents at each stationary emission source were in the range of 3.9-30.0 pg·m-3 (at WHO-TEQ) for dioxins which was lower than other thermal processes such as municipal solid waste incineration. Second, higher chlorinated PCDD/Fs were the dominant congeners. Third, emissions of dioxins were dependent on coking pattern. Stamping coking and higher coking chamber may lead to lower emission. Source

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